I have heard the epoxy many choose to use for the process of filling the intake ports is Devcon. They sell numerous types and I was trying to find the most appropriate. I contacted them and they suggested the Plastic Steel Putty for up to 250 degrees F and the Titanium putty for up to 350 degrees F.

Do you think the Plastic Steel putty would suffice? I already have a 1lb container and would like to use it if possible. I'm hoping the epoxy wouldn't see over 250 degrees since the coolant will be circulating through the housings.

I've never done it but have seen plastic steel used for this. I don't think longevity is the issue with the Devcon as the motors don't tend to last that long anyway!

Thanks for the reply.

Why is it that many people seem to think peripheral ports will not last a good while? If properly built shouldn't they outlast a bridgeport by quite some time?

If you could source housings that never had the intakes cast into them then yes

The filled intake ports deteriorate. Plus you often use more revs than any other config, and wear increases exponentially at high rom!

Mind you, I have had a Devconned PP last 18 months before needing a rebuild

I saw a set of brand new irons in Japan for a peripheral port motor, the irons were from Mazda and came filled, I think you have to know the secret handshake to get stuff like that directly from Mazda...

They used devcon metallic epoxy, but it wasn't all the way filled with that, on the outside of the iron, white silicone was visible, the guy who had it , through a translator, was saying something about there being a problem with adhesion in the curing if the epoxy is to thick, so its done in small amounts, and not all the way through the port...Hope that helps you..I have a pic of it somewhere I will dig up...Maxt

Thanks Maxt! A pic would be a great help.

18 months?



Geez, I ran my 13B PP race engine for 5 years of regular competition before a spun rear bearing necessitated having to tear it down for a rebuild. I'll post some pics of the housings when I get home, which required no more than a wipe over to clean them. Compared to the rotors I looked at in one of the other posts, mine were like new. Again, I'll post a couple of pics for you guys to check out.



Cheers from downunda,

Peter

Here are some photos of the housings showing the peripheral porting.

Thanks, those are nice pics!!!

Anyone else have any they would like to share?

5 years is a good run!

I was using mine as a DD as well as a weekend warrior....10 mpg an all https://www.nopistons.com/forums/pub...IR#>/wacko.png



What can I say? I was young & stoopid https://www.nopistons.com/forums/pub...>/rolleyes.gif

and now you're just old and st.....



Right, Robbomaz?.....

ahhh PP would be nice.... https://www.nopistons.com/forums/pub...DIR#>/wink.png

Here are some photos of the work on my PP engine around the peripheral ports.



Peter

And here's the custom intake manifold. You can see quite clearly the outlines of the intake ports from the housings.

Ok, I understand now. I thought you had the stock intake ports filled. I didn't realize you were referring to the rotor housing around the peripheral intake.

Looks like a good setup. You don't think there is any type of drawback from having the open ports? I suppose turbulence wouldn't be an issue.....hmm, interesting. It must be more reliable than having to worry about epoxy cracking and falling in to the housings https://www.nopistons.com/forums/pub...IR#>/smile.png

I'm not going to have a fancy manifold. I was going to just connect large diameter hose and use that. I could make block off plates for the intake ports on the front and rear housings since they are already tapped but the intermediate has no holes to use on my 12a. Did you tap the housing or were the holes already there? I much prefer the block off plate idea for reliability.

Mazdaracer used a 3rd gen block. It already has that bolt pattern for the intake manifold.

I'll take a couple of snaps of the port side (as opposed to the starboard side?) when I get home from work.



I'm sure the bolt holes were already there to take the manifold plate, as mazdaspeed7 points out.



Cheers, and good luck Heath.



PS. If you want a template of that intake manifold I can trace it up for you. Let me know. Will it fit the 12A?

I appreciate the offer but I don't think the template would work on a 12a. As it stands right now I think I will indeed make block off plates for the front and rear housings and fill in the intake ports on the intermediate since there is no way to secure a block off plate. I'm just going to add the Devcon in small amounts and allow it plenty of time to cure in between. I really don't want to lose an engine because of failing epoxy :(

Was there any kind of buildup you found in the stock intake ports when you broke down your engine? Thanks again for all your help!

A couple of things ...



The engine was very clean when I disassembled it. No build up around the intake ports.



When you apply the DevCon, are you thinking of putting a little on then letting it cure, then putting a little more in? I don't have any experience with that stuff but wouldn't it be better for it all to go in at once so that when it cures it forms a uniform, solid mass. My thinking would be that it may not bond together if the first blob has already dried.



You can block off the end ports but couldn't you drill and tap the middle ports, so that would be less messy and probably look more professional too? Even a pro shop would only charge you a minimal cost to do that. https://www.nopistons.com/forums/pub...IR



Peter

I'll have to take a good look and see if there is enough material to drill and tap. As far as the Devcon is concerned you may be correct. Would it be best to pour it in small amounts and let it fully cure between additions or best to pour it in one large sum? I guess the epoxy chemically cures and does not require air?

If I poured it in small amounts it would probably be best to roughen up the layers before adding additional ones.

If anyone has actually done this then please advise https://www.nopistons.com/forums/pub...R#>/unsure.png

Portside photo as promised: https://www.nopistons.com/forums/pub...DIR#>/cool.png

The hole below the ports on the intermediate housings is the one that may be tricky. I'm going to have to get the opinion of a machinist. There is plenty of room to drill and tap a hole above the ports.

What do you think of this stuff?



http://www.alvinproducts.com/Products/Prod...uggested%20uses

That seems like some really good stuff but I'm not sure about the curing process:

"In order for Hi-Temp Lab-metal to completly harden after a 24 hour air dry time, it must be exposed to a minimum temperature of 425ºF for a period of at least one hour depending on thickness of application."



Wouldn't that high temperature possibly warp the housing?